package edu.self.util;

import java.io.IOException;

import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;

public class SetCharacterEncodingFilter  implements Filter{

	protected String encoding = null; 
	protected FilterConfig filterConfig = null; 
	protected boolean ignore = true; 

	@Override
	public void destroy() {
		this.encoding = null; 
	    this.filterConfig = null; 
	}

	@Override
	public void doFilter(ServletRequest request, ServletResponse response,
			FilterChain chain) throws IOException, ServletException {
		
		if (ignore || (request.getCharacterEncoding() == null)) { 
			String encoding = selectEncoding(request); 
		    if (encoding != null) { 
		        request.setCharacterEncoding(encoding);
		    } 
		} 
		chain.doFilter(request, response); 
	}

	@Override
	public void init(FilterConfig filterConfig) throws ServletException {
		this.filterConfig = filterConfig; 
	    this.encoding = filterConfig.getInitParameter("encoding"); 
	    String value = filterConfig.getInitParameter("ignore"); 
	    if (value == null) { 
	      this.ignore = true; 
	    } 
	    else if (value.equalsIgnoreCase("true")) { 
	      this.ignore = true; 
	    } 
	    else if (value.equalsIgnoreCase("yes")) { 
	      this.ignore = true; 
	    } 
	    else { 
	      this.ignore = false; 
	    } 
	}

	protected String selectEncoding(ServletRequest request) { 
	    return (this.encoding); 
	} 
}
